[mgrimace]

Outside of ecosystem +/-, a different perspective is build/hardware.

I personally moved from a Kobo Aura One -> Kindle Oasis 2. I was originally intending to buy the Forma, but after getting my hands on it at a local Chapters (Canada), I found it definitely matched the complaints in the Kobo Thread. Specifically, dark banding across the button-side, inconsistent lighting, a horribly mushy on/off button that's positioned poorly, and flex-y page-turn buttons. On the contrary, the Oasis 2 was rock-solid build quality, satisfying clicky buttons, and perfectly even lighting (on mine, others have reported different experiences though).

I personally well preferred the Kobo software - it's a small thing but I loved having my covers on the lockscreen, easy series organization, etc.. I also really enjoyed the ComfortLight, and some other features via patches (e.g., full-screen mode). Of note, I do find the inverted mode on the Kindle is a fantastic replacement for bedtime reading - different, but a solid alternative if you do a lot of night reading.

Overall though, since I personally notice hardware and find inconsistent lighting extremely distracting (and I had similar inconsistencies on my Aura One) I went with the Kindle Oasis 2 and find it a better choice - overall it 'disappears' when I read which is the best part.

That's my own experience, with the point being it might also be worth trying to get your hands on them to experience the hardware as well as the software.